From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C434DCF5397 for ; Wed, 23 Oct 2024 14:32:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=TKoI9dEllx1TNgC9xZVCozD6BRiFRJgzuEW3oaX71qI=; b=DUnwfT6FZPlasR3cOFFQY/TKk8 jKJ4tejqIRiyP3OuzKikniJcYCSpry17RcFRzf9vEf2jxWaRD/N4BO0Kd/uupf0TOdXvwfuStZeNn EXpwpRd5He+vRgQjpHPDrvM9sg4dtth22HsF/ESytbOtVa7xk92oY5tPTSl/W2lHw+oQ5lAu4GA+F gAybmGHu85JQzxGjCH4P5rrphxafcowO/YbSeXt+UUtoPkoLsbZBFD5fFtWGMC99b5ZmjlLYt6BHy Q793TV/rOAl8rsMxnzq2zHIdhYj1JCYmwhVAS4mpth8vmhGm3B2ByqWPzY5DTlYiDuSvqzKPcR+C5 hhyER+Hg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1t3cPP-0000000EiMK-00BG; Wed, 23 Oct 2024 14:32:23 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1t3cNd-0000000EhbT-125x for linux-arm-kernel@lists.infradead.org; Wed, 23 Oct 2024 14:30:34 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 2ED895C57F9; Wed, 23 Oct 2024 14:30:28 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9F5EAC4CEC6; Wed, 23 Oct 2024 14:30:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1729693832; bh=DTPT4zl44npMYzjERrEH9EvBCMsinVpzO0mfU1W/K+s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gZZGLJl+iG9JdNz/tDltYSPBH+P1BzVIeOb+X5mKKGdkSzWrFAIDwkXVngoUfzLxe Txo7XVFgUlnmwc4msYAbE94uBGxmYdHMhO4Qx+psH5nrx8ZAM0PBGGCY+tLvvgULSx VBCfOWwe4kx8U2ICOoQus9DH0OBEc7L+k02XMaA9UBKX4PeyTDqihClw36LggcEoYt RlJbMeDI2IdI4oxEy+mstaLK57kwSWlxi5qnzHMfhOAbl20aMkKJQuIuKhxOcD2ah4 Xk6GdgIBTT74600jLyBof/AxR2HNo+cud8fpLegrixWTzdJFo+/VZWRnYoCb4ypW5x inqT+FU0B23ig== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Robin Murphy , Will Deacon , Sasha Levin , joro@8bytes.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev Subject: [PATCH AUTOSEL 6.11 12/30] iommu/arm-smmu: Clarify MMU-500 CPRE workaround Date: Wed, 23 Oct 2024 10:29:37 -0400 Message-ID: <20241023143012.2980728-12-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20241023143012.2980728-1-sashal@kernel.org> References: <20241023143012.2980728-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.11.5 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241023_073033_356241_2B49AD7F X-CRM114-Status: GOOD ( 12.33 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Robin Murphy [ Upstream commit 0dfe314cdd0d378f96bb9c6bdc05c8120f48606d ] CPRE workarounds are implicated in at least 5 MMU-500 errata, some of which remain unfixed. The comment and warning message have proven to be unhelpfully misleading about this scope, so reword them to get the point across with less risk of going out of date or confusing users. Signed-off-by: Robin Murphy Link: https://lore.kernel.org/r/dfa82171b5248ad7cf1f25592101a6eec36b8c9a.1728400877.git.robin.murphy@arm.com Signed-off-by: Will Deacon Signed-off-by: Sasha Levin --- drivers/iommu/arm/arm-smmu/arm-smmu-impl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c b/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c index 9dc772f2cbb27..99030e6b16e7a 100644 --- a/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c +++ b/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c @@ -130,7 +130,7 @@ int arm_mmu500_reset(struct arm_smmu_device *smmu) /* * Disable MMU-500's not-particularly-beneficial next-page - * prefetcher for the sake of errata #841119 and #826419. + * prefetcher for the sake of at least 5 known errata. */ for (i = 0; i < smmu->num_context_banks; ++i) { reg = arm_smmu_cb_read(smmu, i, ARM_SMMU_CB_ACTLR); @@ -138,7 +138,7 @@ int arm_mmu500_reset(struct arm_smmu_device *smmu) arm_smmu_cb_write(smmu, i, ARM_SMMU_CB_ACTLR, reg); reg = arm_smmu_cb_read(smmu, i, ARM_SMMU_CB_ACTLR); if (reg & ARM_MMU500_ACTLR_CPRE) - dev_warn_once(smmu->dev, "Failed to disable prefetcher [errata #841119 and #826419], check ACR.CACHE_LOCK\n"); + dev_warn_once(smmu->dev, "Failed to disable prefetcher for errata workarounds, check SACR.CACHE_LOCK\n"); } return 0; -- 2.43.0